Adaptec AAA-UDMA RAID Controller Review
A few months ago I noticed an interesting new product on Adaptec's Web site: an Ultra DMA RAID controller that was not only a full hardware RAID but also supported RAID 5. I immediately wanted to test this device, and after several months of attaining the appropriate hardware and weeks of benchmarking, it is finally time to write up this review of it. The controller is the AAA-UDMA, a four-channel UDMA/66 RAID controller supporting up to four hard drives in RAID 0, RAID 1, RAID 0/1, and RAID 5 configurations.

It comes with a 2 megabyte ECC EDO DIMM as a cache buffer, and the slot supports up to a 64MB module of the same type for increased performance.

Adaptec makes it clear on the box and in the product literature that the AAA-UDMA is meant for entry-level servers. This should come as no surprise to those familiar with RAID systems. SCSI controllers can have 15 or more devices per channel (depending on exactly which type of SCSI is used), and since arrays can span multiple channels and even multiple cards in high-end configurations, SCSI RAID arrays consisting of tens of drives are not uncommon in large servers.

And since even a single-channel SCSI controller can hold many more than four drives, this ATA solution is strictly intended for small servers for those on a budget. The box says such a server should support no more than 25 users, so this is the kind of device a company might consider for use in a workgroup server. Despite Adaptec's recommendation, it seems from the specifications that this card would also be great for high-end desktop or workstation systems that need a lot of hard disk throughput and redundancy, but can't afford a significantly more expensive SCSI array.

The retail box contains the
following items: the full-length PCI adapter itself; a card with installation
tips, Adaptec's contact information, and a registration card; serial number
stickers (one to put on the registration card, one to put somewhere that's
easily accessible so you can read the number should you need to call technical
support); four UDMA/66 cables; an installation and hardware guide; a user guide
for the Adaptec CI/O management software; the CI/O management software on
CD-ROM; one floppy disk with the BIOS, firmware, and flashing utilities; two
floppies used to boot and configure the system when setting up the array as the
boot device; three floppies with drivers for Windows NT 4, Windows 2000, and
NetWare; and finally, the ever-present licensing agreement for using the
software.

As mentioned above, the card also comes equipped
with a 2-megabyte unbuffered ECC EDO DIMM for cache, and can support up to a
64-megabyte module. The card supports up to four hard disks and has one ATA
channel per disk. Note that the card does not support any devices other than
hard disks, and it has only internal connectors. Interestingly, the card
supports only UDMA/66, not the newer UDMA/100.

My assumption is that Adaptec started designing the
card a while back, and even though its design was completed earlier this year,
they spent several months testing it and did not release it until recently.
Perhaps a similar UDMA/100 card is in the works. In any case, no single ATA
drive can reach throughput speeds of 66 megabytes per second anyway, so it's not
a big issue, and ATA/100 drives will work fine with the card.